JPS6359043B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel cutoff control device using a microcomputer powered by a battery.

Conventionally, there have not been many fuel cutoff control devices that use batteries as a power source. In addition, many common devices that use batteries as a power source, if the battery voltage drops,
For example, as can be seen in devices that already have a display, such as watches and calculators, it is only when the user notices that the time error has increased or calculations are no longer possible that the user realizes that the original function has been lost. It's summery.
As described above, currently there is no means to reliably grasp and notify the operating state of equipment based on the battery voltage level.

The function of a fuel cut-off control device is to install it at the entrance of a gas supply line, such as in gas meters in each home, and automatically supply fuel if it is determined that there is an abnormality based on the flow rate, such as when there is a continuous flow of gas. Such equipment must be maintained in monitoring operation throughout the year. However, this type of device is installed far away (outdoors) and the user cannot frequently check the presence or absence of the battery, so when the battery voltage drops, it is necessary to reliably notify the user of the voltage drop and maintain this information. Must be. In addition, a self-holding electromagnetic device is used in a shutoff device using a battery as a power source in order to reduce power consumption, and even when the battery voltage drops, the current state of the shutoff valve is maintained. Therefore, for example, when a means such as a reset switch is provided to reset the low battery voltage display, once the display is reset, the
Although it appears to be operating normally (in this case, despite the battery voltage drop), there is a risk that the battery will not be replaced and the year-round monitoring function will be impaired.

The present invention is a fuel cutoff control device with a battery voltage check function and low battery display that prevents erroneous resets of the low battery display, mistakes in replacing defective batteries, etc., and ensures the year-round monitoring function of the fuel cutoff control device. The aim is to be able to maintain it.

In order to achieve the above objective, the basic idea is to have a voltage detection section for the battery voltage and a main control section that judges the signal from the voltage detection section at every predetermined time and every time the battery voltage is reset. With this configuration, the display can be automatically reset only when the battery is replaced with a normal battery.

Furthermore, the present invention has an additional object of the present invention, in which a battery voltage check function is added, to operate the notification means reliably when the voltage drops, and to prevent erroneous shut-offs and erroneous indications.

In order to achieve the above object, the present invention includes a voltage detection part of a battery power supply, a cutoff part, a power supply opening/closing part that opens and closes the power supply to the display part, and a main body that drives the display part and the power supply opening/closing part when the voltage drops. The basic configuration includes a control section, and with this configuration, the states of the cutoff section and the display section can be stably maintained.

Hereinafter, one embodiment of the present invention will be described using the drawing of FIG. In addition, in FIG. 2, the same numbers are attached to the same contents as in FIG. 1.

In the figure, 1 is a power supply unit consisting of a battery, 2 is a reset unit that applies a reset signal to the RST terminal of the main control unit based on the battery voltage, and 3 is a voltage that compares the battery voltage with a predetermined minimum operating voltage of the control circuit. 4 is a voltage detection switching unit that opens and closes the power supply to the voltage detection unit; 5 is a main control unit consisting of a microcomputer; 6 is a self-holding display unit that displays a battery voltage drop; 7 is a fuel supply path. A shutoff section 8 is a sensor input section that inputs a fuel flow signal.

Next, the operation of the above configuration will be explained.

First, when the power supply section 1 is turned on, the reset section 2 gives a reset signal to the main control section 5 to initialize the operation of the main control section 5. The main control section 5 is comprised of a microcomputer, measures the fuel flow rate signal from the sensor input section 8, and when an abnormal flow rate is detected, drives the cutoff section 7 to cut off the fuel supply path. Also,
It has a repeat timer function, and periodically (for example, every 24 hours) drives the voltage detection opening/closing section 4 to put the voltage detection section 3 into operation, and inputs the signal from the voltage detection section to check the battery voltage. At the same time, the operation of the voltage detecting section 3 is stopped. At this time, if the voltage check result indicates a voltage drop state, the display section 6 is driven. Since the power consumption of the voltage detection unit 3 is zero when driving the display unit 6, the display unit can be operated reliably even when the battery is close to its end of life and its internal resistance is increasing. . This is particularly effective when using a self-holding type display unit that inverts a magnet, which requires a relatively large current, because the winding resistance for supplying inversion energy is low. In this way, the display section 6 is operated reliably to maintain the voltage drop display state. After that, the user looks at the display section 6 and replaces the battery. At this time, by removing the battery and reinserting it, the microcomputer of the main control unit 5 is initialized by the signal from the reset unit 2, and the voltage detection opening/closing unit 4 is driven, and the voltage detection unit 3 is It inputs a signal to check the presence or absence of battery voltage, and if a normal voltage is detected, outputs a signal to reset the voltage drop display on the display section 6. 9 is called a control section. Therefore, if a mistake is made in replacing the battery with a defective one, the voltage drop display will not be reset, allowing the user to know about the mistake in replacement. In addition, the user can reset the voltage drop display simply by inserting a normal battery, so maintenance can be performed reliably with simple work.

FIG. 2 shows a specific embodiment based on the block diagram of FIG. 10 is an IC that checks the battery voltage and detects the voltage of the Vin input, and the battery voltage>
At the set voltage, the output is high, and when the battery voltage ≦ the set voltage, the output is low. 11 is a transistor for opening and closing the power supply of IC 14, and is opened and closed by a signal from the main control terminal _O1 . Reference numeral 12 denotes a reed switch for measuring the flow rate of fuel, and the transistor 17 responds to the operation of the reed switch 12, which is installed close to a meter such that a magnet moves back and forth depending on the gas flow rate. Therefore, the main control section 5 can measure the flow rate of fuel based on the number of pulses input to the input terminal of _I2 . 14 and 15 are a magnetic indicator 18, a set winding 16, and a reset winding 17.
This is a transistor for driving a display device having. 19 is a transistor for driving the cutoff valve 20.

Further, another embodiment of the present invention will be explained with reference to FIG.

Reference numeral 1 denotes a power supply section consisting of a battery, 2a a power switching section consisting of a self-holding circuit, 3 a voltage detection section that compares the battery voltage with a predetermined minimum operating voltage of the control circuit, and 4 a power supply for the voltage detection section. 5 is a main control unit consisting of a microcomputer, 6 is a self-holding display unit that displays battery voltage drop, and 7 is a shutoff unit consisting of a self-holding electromagnetic valve that shuts off the fuel supply path. , 8 is a sensor input section for inputting a fuel flow rate signal.

First, when the power supply section 1 is turned on, the power supply opening/closing section is reset and maintained in the closed state. Therefore, power is supplied to the display section 6, the cutoff section 7, and the control circuit 9.
The main control section 5 is composed of a microcomputer, and measures the fuel flow rate signal from the sensor input section 8, and when an abnormal flow rate is detected, drives the cutoff section 7 to cut off the fuel supply path. It also has a repeat timer function, and periodically (for example, every 24 hours) drives the voltage detection opening/closing section 4 to put the voltage detection section 3 into an operating state, and inputs a signal from the voltage detection section. At the same time as checking the presence of battery voltage,
The operation of the voltage detection section 3 is stopped. At this time, if the voltage check result indicates a voltage drop state, the display section 6 is driven. When driving the display unit 6, the voltage detection unit 3
Since the power consumption of the battery has become zero, the display section can be reliably operated even when the battery is nearing the end of its life and its internal resistance is increasing. This is particularly effective when using a self-holding type display unit that inverts a magnet, which requires a relatively large current, because the winding resistance for supplying inversion energy is low. Furthermore, when the voltage drops,
After driving the display section 6 for a predetermined time, the power supply opening/closing section 2
By driving the power supply circuit of the display section 6 and cut-off section 7, the operating state of the display section 6 and cut-off section 7 is reliably maintained, thereby preventing situations such as erroneous display or erroneous cut-off. It can be prevented. Further, at this time, the power supply to the control circuit 9 may be stopped. After that, when the user looks at the display section 6 and replaces the battery, the power switching section 2 is reset, and the power supply circuits of the power supply section 1, the display section 6, and the display section 7 are closed, and the control device is turned off. Operation is resumed. At this time, when the main control unit 5 is initialized,
By checking the battery voltage and outputting an inverted output from the display section 6, the display section 6 can be reset without bothering the user.

FIG. 2 shows a specific embodiment based on the block diagram of FIG. The same numbers as in FIG. 3 indicate the same contents. Reference numeral 10 denotes a coil of a self-holding type relay, and when the output terminal _O2 of the main control section 5 becomes low and the transistors 12 and 13 conduct, the contact 10' remains open. This operation is performed when a drop in battery voltage is detected. 11 is a reset switch for a self-holding relay, and when the battery is replaced, the contact 11' is temporarily moved to the normally open contact, and at this time, current flows in the reverse direction to the relay coil 10, closing the contact. 1
0' returns to the normally closed side. 14 is an IC that checks the battery voltage and detects the voltage of the Vin input, and the battery voltage>
The output is high when the set voltage is set, and the output is low when the battery voltage ≦ the set voltage. 15 is IC1
This transistor is used to open and close the power supply of No. 4, and is opened and closed by the signal from the main control terminal _O1 . Reference numeral 16 denotes a reed switch for measuring the flow rate of fuel, which is installed close to a meter in which a magnet moves back and forth depending on the gas flow rate, for example, and a transistor 17 responds to the operation of the reed switch 16. Therefore, the main control unit 5 can measure the fuel flow rate based on the number of pulses input to the input terminal of _I2 . 18,19
is a transistor for driving a display having a magnetic display 22, a set winding 20, and a reset winding 21. 23 is a transistor for driving the cutoff valve 24.

As described above, the fuel cutoff control device of the present invention provides the following effects.

By configuring a battery voltage detection section, a voltage drop display section, and a main control section whose operation is initialized by the battery voltage, it eliminates erroneous resets of battery voltage drop displays and battery replacement errors, and prevents battery voltage drop. It is possible to reliably maintain the display state and eliminate mistakes in grasping the state of functional stoppage of the control device due to a drop in battery voltage. Furthermore, since the battery voltage drop display can be reset simply by replacing the battery with a normal battery, maintenance can be done easily.

Furthermore, the battery voltage is checked intermittently.
Since the voltage detection section, the display section, and the power switching section are operated discretely when the voltage drops, each can be operated reliably even when the internal resistance of the battery is large when the voltage drops. Further, after detecting a decrease in battery voltage, power is not supplied to the display section and the cutoff section, so that future erroneous display and erroneous cutoff can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a fuel cutoff control device according to an embodiment of the present invention, FIG. 2 is a specific circuit diagram of FIG. 1, and FIG. 3 is a block diagram of a fuel cutoff control device according to another embodiment of the present invention. The block diagram, FIG. 4, is a specific circuit diagram of FIG. DESCRIPTION OF SYMBOLS 1... Power supply part, 2... Reset part, 2a... Power switching part, 3... Voltage detection part, 5... Main control part,
6...display section, 7...blocking section, 8...sensor input section.

Claims (1)

[Scope of Claims] 1. A power source section consisting of a battery, a sensor input section that inputs a fuel flow rate signal, a cutoff section consisting of a self-holding electromagnetic valve that cuts off a fuel supply path, and a battery voltage drop display. a display section, a voltage detection section that compares the voltage of the battery with a predetermined voltage and outputs a signal to the main control section, a reset section that gives a reset signal to the main control section based on the battery voltage, the display section, and the cutoff section. The sensor input section has an output terminal for driving each of the sections, an input terminal for inputting a signal from the voltage detection section, and a reset terminal for performing a reset operation depending on a signal from the reset section. When the signal reaches a preset flow rate, the cutoff section is driven, and after determining the input signal from the voltage detection section at predetermined intervals, the display section is driven when the voltage drops, and the reset operation is performed. a main control section that determines an input signal from the voltage detection section and resets and drives the display section. 2. A power supply section consisting of a battery, a sensor input section that inputs a fuel flow rate signal, a cutoff section that cuts off the fuel supply path, a display section that displays a battery voltage drop, and a device that compares the voltage of the battery with a predetermined voltage. a voltage detection section that outputs a signal to the main control section; a power supply switching section that opens a power supply circuit to the cutoff section and the display section; and each of the display section, the power supply switching section, and the cutoff section. It has an output terminal for driving the sensor input section, an input terminal for inputting a signal from the voltage detection section, and after determining the input signal from the voltage detection section, drives the display section when the voltage decreases and A fuel cutoff control device consisting of a main control section that drives a power supply opening/closing section.